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This article describes a chairside technique to correct inappropriate occlusal vertical dimension as well as the inaccurate anterior-posterior tooth set-up of a maxillary immediate complete denture. When fabricating an immediate denture, the inability of a wax-denture trial and the potential for unpredictable complications during surgery, compromised esthetics and function of an immediate complete denture may pose a clinical problem, which needs instant correction. The technique described can provide an alternative method to correct and deliver a definitive immediate complete denture on the day of surgery.

Objectives/Hypothesis Children with bilateral true vocal fold immobility (BTVFI) may present with significant airway distress necessitating tracheostomy. The objective of this study was to review our preliminary experience with the anterior–posterior cricoid split (APCS), an endoscopic intervention used as an alternative to tracheostomy in children with BTVFI. Study Design Multicenter review. Methods A review of patients undergoing endoscopic APCS for BTVFI at four institutions was performed. Patients were evaluated for the ability to ventilate without the requirement for tracheostomy or reintubation. Additional data extracted included the duration of intubation following APCS, the requirement for additional procedures, and demographics. Surgical success was defined as the ability to avoid tracheostomy and to cap or decannulate without respiratory symptoms if a tracheostomy was present prior to APCS. Results Nineteen APCS procedures were performed between October 2010 and June 2016. There were 12 male patients, the mean age at APCS was 4.7 months. BTVFI was primarily idiopathic (58%) and associated with other comorbidities (74%). All patients were candidates for tracheostomy prior to APCS. Fourteen patients (74%) were considered surgical successes. Of the unsuccessful patients, three (66%) required tracheostomy following APCS, and one was treated with a posterior cartilage graft. There was one nonsurgical mortality greater than 2 months after APCS and thought to be unrelated to the airway. Conclusions Endoscopic APCS appears to be a safe and effective intervention for pediatric BTVFI. Under the correct circumstances, this can be performed as a single procedure, obviating tracheostomy. Further study is warranted. Level of Evidence 4. Laryngoscope, 128:257–263, 2018

Measurements made on routine A-P radiographs can predict strength/quality of the proximal humerus, as shown in terms of two easy-to-measure parameters: cortical index (CI) and mean-combined cortical thickness (MCCT). Because of high variability inherent when using established methods to measure these parameters, we describe a new orientation system. Using digitized radiographs of 33 adult proximal humeri, five observers measured anatomical reference locations in accordance with: (1) Tingart et al. (2003) method, (2) Mather et al. (2013) method, and (3) our new humeral head Circle-Fit method (CFM). The Tingart and Mather methods measure CI and MCCT with respect to upper and lower edges of 20 mm tall rectangles fit to a proximal diaphyseal location where endosteal (Tingart) or periosteal (Mather) cortical margins become parallel. But high intra- and inter-observer variability occurs when placing the rectangles because of uncertainty in identifying cortical parallelism. With the CFM an adjustable circle is fit to the humeral head articular surface, which reliably and easily establishes a proximal metaphyseal landmark (M1) at the surgical neck. Distal locations are then designated at successive 10 mm increments below M1, including a second metaphyseal landmark (M2) followed by diaphyseal (D) locations (D1, D2 …D6). D1 corresponds most closely to the proximal edges of the rectangles used in the other methods. Results showed minimal inter-observer variations (mean error, 1.5 ± 1.1mm) when the CFM is used to establish diaphyseal locations for making CI and MCCT measurements when compared to each of the other methods (mean error range, 10.7 ± 5.9 to 13.3 ± 6.7 mm) (p

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effects (benefits and harms) of different surgical techniques for treating type II superior labrum anterior posterior lesions.

Purpose: To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Methods: Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior–inferior (SI) internal and anterior–posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Results: Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01–0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01–0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%–10.8%) of gate width (range 1.6–3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Conclusions: Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients.

The identification of Harris lines through radiographic analysis has been well-established since their discovery in the late nineteenth century. Most commonly associated with stress, the study of Harris lines has been fraught with inconsistent identification standards, high levels of intra- and interobserver error, and the inevitability of skeletal remodelling. Despite these methodological challenges, the use of Harris lines remains an important contributor to studies of health in archaeological populations. This research explores the radiographic process, specifically orientation and how Harris lines are initially captured for study. Using the Black Friars (13th–mid 17th centuries) skeletal sample from Denmark, 157 individuals (134 adults; 23 subadults) were radiographically analyzed in both an anterior–posterior (A–P) and medial–lateral (M–L) view for the left and right radii and tibiae. Based on the current methodological standards within the literature, it was hypothesized that the A–P view would provide the best resolution and visualization of Harris lines. The results, however, show that the number of lines visible in the M–L view were significantly higher than those visible in the A–P view; inferring that the M–L view is superior for the study of Harris lines. Am J Phys Anthropol 156:141–147, 2015 © 2014 Wiley Periodicals, Inc.

Aim The aim of this study is to look at the weak points of tension-free vaginal mesh (TVM) operation for pelvic organ prolapse by reviewing recurrent cases. Methods Five hundred and twenty-six transobturator TVM operations were performed at the University of Occupational and Environmental Health hospital from August 2006 to December 2011. Thirty-seven patients with pelvic organ prolapse quantification (POP-Q) stage II or higher after their initial operations were diagnosed as recurrent and were enrolled in the present study. The patients' characteristics, procedures of the initial and second operations, and the recurrence rates in the pelvic organs were retrospectively reviewed. Results The median age, parity and body mass index of the patients were 66.5 years (range, 48–80), 2.2-times (range, 1–5) and 24.1 kg/m2 (range, 17.6–32.1), respectively. The mean/median follow-up periods of the whole group were 29.7/35.9 months and the recurrent prolapse rate was 7.0% (37/526 cases). We performed reoperations in eight cases (8/526 cases; 1.5%). The median recurrent period after the initial operations was 6.9 months (range, 1–24). All recurrent cases showed severe prolapse with POP-Q stage III to IV before the initial operations. The uterus showed the most frequent recurrent prolapse after anterior posterior TVM or anterior TVM. Conclusion Because the uterus is the most recurrent organ after TVM operations, TVM operations may not be sufficient for apical suspension.

Because DXA is a projection technique, anterior–posterior (AP) measurements of the spine include the posterior elements and the vertebral body. This may be a disadvantage because the posterior elements likely contribute little to vertebral fracture resistance. This study used QCT to quantify the impact of the posterior elements in DXA AP spine measures. We examined 574 subjects (294 females and 280 males), age 6–25 yr, with DXA and QCT. QCT measures were calculated for the cancellous bone region and for the vertebral body including and excluding the posterior elements. DXA data were analyzed for the entire L3 vertebra and for a 10-mm slice corresponding to the QCT scan region. BMC and BMD were determined and compared using Pearson's correlation. The posterior elements accounted for 51.4 ± 4.2% of the total BMC, with a significant difference between males (49.9 ± 4.0%) and females (52.8 ± 3.9%, p < 0.001). This percentage increased with age in younger subjects of both sexes (p < 0.001) but was relatively consistent after age 17 for males and 16 for females (p > 0.10). DXA areal BMD and QCT volumetric BMD correlated strongly for the whole vertebra including the posterior elements (R = 0.83), with BMC measures showing a stronger relationship (R = 0.93). Relationships were weaker when excluding the posterior elements. We conclude that DXA BMC provides a measure of bone that is most consistent with QCT and that the contribution of the posterior elements is consistent in young subjects after sexual maturity.

This review aims to propose an integrated model for dorsal-ventral and anterior-posterior development of Xenopus. Fertilized Xenopus eggs contain two determinants, a vegetal half endomesodermal determinant and a vegetal pole dorsal determinant (DD). The organizer forms in the specific intersection of the determinants, in a cell-autonomous manner. At late blastula, different combinations of the determinants form three embryonic domains, the competent animal domain, the organizer domain, and the entire vegetal half domain. These three domains cooperatively form dorsal-ventral and anterior-posterior axes: the organizer domain secrets dorsal inducing signals which induce or ‘activate’ the competent animal domain to form anterior-most neural tissues. The vegetal non-dorsal-marginal domain secrets posteriorizing signals, which ‘transform’ the anterior properties of the neural tissue to posterior properties.

We examined sex differences in general joint laxity (GJL), and anterior-posterior displacement (ANT-POST), varus-valgus rotation (VR-VL), and internal-external rotation (INT-EXT) knee laxities, and determined whether greater ANT and GJL predicted greater VR-VL and INT-EXT. Twenty subjects were measured for GJL, and scored on a scale of 0-9. ANT and POST were measured using a standard knee arthrometer at 133 N. VR-VL and INT-EXT were measured using a custom joint laxity testing device, defined as the angular displacements (deg) of the tibia relative to the femur produced by 0-10 Nm of varus-valgus torques, and 0-5 Nm of internal-external torques, respectively. INT-EXT were measured during both non-weight-bearing (NWB) and weight-bearing (WB = 40% body weight) conditions while VR-VL were measured NWB. All laxity measures were greater for females compared to males except for POST. ANT and GJL positively predicted 62.5% of the variance in VR-VL and 41.8% of the variance in WB INT-EXT. ANT was the sole predictor of INT-EXT in NWB, explaining 42.3% of the variance. These findings suggest that subjects who score higher on clinical measures of GJL and ANT are also likely to have greater VR-VL and INT-EXT knee laxities.

Objective To determine the relationship between gestational age and renal pelvic anterior–posterior diameter and the feasibility of developing gestational age–specific thresholds for the diagnosis of mild pyelectasis. Methods Cross-sectional study of 420 singleton fetuses between 16 and 39 weeks' gestation. The mean renal AP diameter as a function of gestational age was determined using fractional polynomial regression models and centile plots were generated. Assessment of goodness of fit for each regression model was performed. Results There was a positive correlation between gestational age and renal pelvic AP diameter (Pearson's Correlation Coefficient 0.65). Using the derived mean and standard deviations of renal AP diameter, gestational-age specific 95% reference levels were generated. The sensitivity, specificity, positive, and negative predictive values of using the gestational age-specific cutoffs for predicting persistent postnatal renal anomaly were 80%; 99%; 29%; and 99% respectively. Conclusion There is a positive correlation between gestational age and renal pelvic AP diameters. Reliable gestational age-specific renal AP thresholds for diagnosis of pyelectasis are provided. Copyright © 2003 John Wiley & Sons, Ltd.

The tension applied to the anterior cruciate ligament (ACL) graft at time of fixation is thought to influence graft healing, knee kinematics, and joint contact forces; however, the optimal tensioning procedure remains unclear. An animal model provides a means by which the effect of graft tensioning on healing can be studied. Prior to using the model, the relationship between graft tensioning and knee kinematics at time of surgery should be established. Our objective was to explore the relationship between graft tensioning and anterior-posterior (A-P) laxity of the reconstructed goat knee. Eight cadaver knees were tested. The A-P laxity values of the intact knee were measured with the knee at 30 degrees, 60 degrees. and 90 degrees flexion. The ACL was then severed and the laxity measurements were repeated. The ACL was reconstructed using a bone-patellar tendon-bone autograft. The laxity measurements were repeated for nine different tensioning conditions; three tension magnitudes (30, 60, and 90 N), each applied with the knee at three angles (30 degrees, 60 degrees and 90 degrees). Both graft tension and the knee angle at which it was applied produced significant changes on A-P laxity values. An increase in tension reduced laxity values. A tension level of 60 N applied with the knee flexed to 30 degrees was the best combination for restoring normal A-P laxity values at all knee angles tested.

The molecular mechanisms that drive the development of embryonic tissues are being uncovered rapidly. One such fascinating example is the development of the forebrain, the most anterior part of the nervous system. In this review, we will discuss the mechanisms that induce the formation of the forebrain in multiple vertebrate systems, placing emphasis on a recent article published by Grinblat et al. ((1)) Using zebrafish as a model system, these authors combine elegant embryological manipulations with the use of early markers of the presumptive forebrain, to show that initial induction and patterning of this tissue occurs near the onset of gastrulation. In addition, their results confirm observations made in other systems that planar signals, those traveling in the plane of the ectoderm, are involved in forebrain induction and patterning.

Purpose: To determine the effects of patient separation on absolute dose and dose distribution in patients undergoing pelvic radiotherapy on TomoTherapy. Methods: An Alderson RANDO phantom with 4cm of bolus was imaged on a CT simulator and the resulting scans were contoured as a whole pelvic case. Using TomoTherapy Planning Station, the plan was designed to give 45 Gy to 95% of the treatment volume in 25 fractions. TomoTherapy MVCT scans were performed on the RANDO phantom with 2cm and 4cm of bolus removed to simulate visible changes in a patient's anatomy. The MVCT images were rigidly registered with planning CT images on TomoTherapy Planned Adaptive. The original fluence was recalculated on the MVCT images and changes in dose distribution due to patient separation were quantified by the changes in DVHs for the target volume and the organs at risk. Results: Patient separation difference equivalent to 2cm and 4cm in anterior-posterior direction resulted in an increase of the PTV D50 and maximum PTV dose of 5.6%, 6.2% for 2cm and 7.7%, 10.4% for 4cm, respectively. For the 2cm change, D50 and maximum doses to organs at risk increased by 6.5%, 7.1% in the bladder, 4.9%, 4.8% in the rectum, and 5.3%, 6.6% in the bowel. For the 4cm change, D50 and maximum doses increased by 10.7%, 12.2% in the bladder, 5.9%, 6.1% in the rectum, and 7.7%, 10.1% in the bowel. Conclusion: This research indicates that, without any changes to the structures, patient separation in the anterior-posterior direction can affect the dose distribution for the PTV and organs at risk. These results can assist physicians in determining if obtaining a new CT simulation set and replanning is necessary for pelvic patients on TomoTherapy.

Purpose: To compare lung dose distributions for two common techniques of total body photon irradiation (TBI) at extended source‐to‐surface distance, with and without tissue density correction (TDC). Lung dose correction factors as a function of lateral thorax separation are approximated for bilateral opposed TBI (supine), similar to those published for anterior‐posterior (AP‐PA) techniques in AAPM Report 17. Methods: 3D treatment plans were created retrospectively for eight patients treated with bilateral TBI, and for whom CT data had been acquired from the head to mid‐thigh. These plans included bilateral opposed and AP‐PA techniques, each with and without TDC, using source‐to‐axis distance of 377 cm and largest possible field size. Results: On average, bilateral TBI requires 40% more monitor units than AP‐PA TBI due to increased separation. Calculation of midline thorax dose without TDC leads to dose underestimation of 17% on average (st. dev. 3%) for bilateral TBI. Lung dose correction factors (CF) are calculated as the ratio of mid‐lung dose (with TDC) to midline thorax dose (without TDC). Bilateral CF generally increase with patient separation, with high variability. However, bilateral CF are 4% (st. dev. 2%) higher than the same corrections calculated for AP‐PA TBI. On average, mid‐lung dose is 4% (st. dev. 3%) lower in bilateral TBI than in AP‐PA TBI. However, maximum lung dose is higher with bilateral TBI (up to 30% higher than prescribed, per patient) due to the absence of arm tissue blocking the anterior chest. Conclusions: Dose calculations for bilateral TBI without TDC are incorrect by up to 21% in the thorax. Bilateral lung CF may be calculated as 1.04 times the values published in Table 6 of AAPM Report 17, though a larger patient pool is necessary to better quantify this trend. Bolus or other compensation will reduce lung maximum dose in the anterior thorax.

Purpose: To quantify the translational and rotational setup differences between laseres on skin markers and bony references through X‐ray Brainlab Exactrac system for patients under pelvic treatment. Methods: 12 patients were initially localized via Exactrac and then received the isocenter laser projection marks on their skin. Over the course of treatment patients were daily localized by localization lasers and skin marks and then a pair of Brainlab Exactrac X‐rays were taken and registered to planning Digital Reconstructed Radiographies (DRRs) in order to calculate the translational and rotational patient shifts. 6D Robotic couch were used to apply shifts. Individual and population statistical analysis of those shifts were performed. Results: The average mean shifts for all directions (lateral, longitudinal and vertical) were close to zero, −0.6mm, −0.3mm and 1.6mm respectively. The average translational standard deviations were: lateral 2.7mm (ranging from 1.9 to 4.6mm), longitudinal: 2.3mm (1.0 to 4.4mm), and vertical: 3.5mm (1.3 to 5.0mm). For all patients studied the mean lateral angular shift (pitch) was always positive (mean 1.1°, ranging from 0° to 3.8°), while the overall longitudinal angular shift (roll) and vertical rotation were −0,1° (SD=0,6°, varying from −0,7° to 1.3°) and 0.0° (SD=0,4°, −0,5° to 0,9°) respectively. Conclusion: The low value of overall mean translational shift indicates there is no significant systematic error for the studied patients. Anterior Posterior direction is the most sensitive to daily differences between lasers and Exactrac. Recurrent positive mean lateral angular shift for all patients might be related to table top sagging and its relation to patient weight needs to be further investigated. Patient localization by skin markers may lead to significant differences compared to bony localization and such discrepancies must be considered for PTV margins. Patient positioning via bony references with Exactrac may potentially reduce PTV margins and consequently side‐effects.

Purpose:CT can contribute over 50% of radiation dose in the whole body (WB) PET/CT scan. Tube current modulation (TCM) is a standard technique for reducing CT radiation dose to the patient by changing the tube current with the patient size, and is controlled by a very low‐dose scoutscan, which assumes the patient is positioned at the center of the CT gantry opening. However, most patients are not positioned at the center due to practicality or to avoid claustrophobic or to reduce time of radiation exposure from the patient to the technologist. We study the impact of the AP and PA scout scans to the patient radiation exposure from CT.Methods: Ina retrospective study of 200 patients, each received two WB PET/CT scans: one with AP, and the other one with PA. The helical CT with TCM and PET acquisitions were identical in both scans. Separation of the two scans was about 10 months in average. The scans were performed on four GE PET/CT scanners: three 16‐ and one 64‐slice with the same TCM settings. The 200patients were selected for the same scan coverage and similar body weight (difference = 3 kg). The tube current in each slice and average exposure tothe patient were recorded and compared. Results: The AP scout caused lower radiation dose on 94% of the patients. Both the tube current, and radiation exposure were reduced by 46±30 mA and 1.6±1.0 mGy, respectively. The effective radiation dose is reduced by 1.7±1.2 mSv. These results were statistically significant (p

Purpose: To compare dose distributions for small animal radiotherapy performed on a microCT scanner with multiple 120kV beams and a single‐field irradiator with a 200kV beam. Materials and Methods: A microCT scanner with a maximum x‐ray tube potential of 120kV and a single‐field irradiator operating at 200kV were modeled in the EGSnrc/BEAMnrc Monte Carlo code. The models were validated using dose in air and depth dose curves in solid water for various beam sizes measured with an ionization chamber and gafchromic films. Treatment plans for a mouse with subcutaneous teratoma and a mouse with a spontaneous lungtumor were created for both the microCT scanner and the single‐field irradiator. On the microCT, the teratoma treatment was prescribed as tangential 80° and 180° beams and lungtumor treatment consisted of eighteen beams equally spaced between 90° and 270°. On the single‐field irradiator, the mice were planned with a left lateral beam and an anterior posterior beam, respectively. The 5Gy dose to the PTV and the dose to critical structures were calculated in the EGSnrc/DOSXYZnrc code. Results: In both cases, the dose distributions achieved with the microCT scanner using a 120kV beam were superior to the dose calculated for a single 200kV beam. The teratoma case showed 4Gy dose to 30% of the left lung whereas the dose to all critical structures on the microCT scanner was below 0.2Gy. In the case of the lungtumor, the dose to the spinal cord and right lung is considerably larger for the single‐field irradiator plan. Left lung and heart are completely spared in the single‐field treatment, however, the dose to these structures is below 1.5Gy in the microCT plan. Conclusions: This work demonstrates that small animal radiotherapy on a microCT scanner yields better critical organ sparing and is therefore preferred over single‐field irradiator radiotherapy.

Coherence and cross-phase-spectral analysis of EEG were applied to photo-sensitive subjects to investigate the mechanism of the generalization of photo-induced paroxysms. Coherence values were high between frontal (F) and central (C) in resting records and between F-C in EEGs revealing harmonic responses, where the coherence values of F-O (occipital) were also high, and the waves of F preceded those of O. In cases of occipital-localized 3/6 Hz (poly) spike-waves, discharges of O preceded those of F. During the stage of generalized paroxysms, discharges were highly cohered between all electrodes. Discharges of F preceded those of O, and appeared to play as a generator. Two conditions with clinical symptoms had higher frequencies (greater than or equal to 12 Hz) and shorter time lags (less than or equal to 5 msec) than conditions without symptoms.

Investigated the effects of discrete brain lesions on MMPI performance in well-matched samples of patients with anterior and posterior injuries. Because of the nature of the samples and careful matching for potentially confounding variables, particular emphasis could be given to the study of brain-behavior relationships. Patients with posterior lesions produced a significantly more abnormal composite MMPI profile, had a consistent tendency to produce elevated (70+) individual MMPI scales, and had individual profiles that were universally rated as abnormal using standard criteria. The differential MMPI patterns exhibited by these two samples were compatible with traditionally held clinical hypothesis with regard to distinct personality differences secondary to focal lesions in the caudal plane. It is our conclusion that lesion caudality does have a differential effect upon MMPI performance when factors such as cognitive, motor, and sensory defects are controlled adequately. The implications are that this effect is locus specific and is not necessarily related to the degree of other neurobehavioral impairment, as has been hypothesized previously.

This study examined and compared lateral and anterior-posterior (A-P) mandibular position discrimination for a group of twenty normal subjects (mean age = 26 years). A specially designed and constructed sliding scale required subjects to position their mandible precisely in the horizontal plane and to try to discriminate differences in the control of their mandibular position. The results revealed that subjects are more sensitive in detecting changes in the lateral positioning of their mandible than in the A-P positions. Subjects' difference limen (DL) values (threshold of discrimination between two positions) in detecting changes in mandibular position to the right of centre was 1.59 mm, and to left of centre was 1.41 mm. Subjects' DL values obtained with the mandible forward, and back of, the reference position were 1.39 and 2.61 mm respectively.

Blood pressure was measured at both ends of the heart of Pyura praeputialis (Heller) after removing the tunic. For posterior anterior heart waves average upstream pressures were 23–25 mm H2O (positive): corresponding downstream pressures averaged 8 mm H2O (negative). For anterior posterior waves average upstream pressures were 17–18 mm H2O (+) and downstream values were 7–8 mm H2O (-). Maximum pulse amplitudes recorded were about 30 mm H2O (upstream). Speed of the peristaltic wave was 25-31 mm/s. In one experiment the speed was demonstrably different over the two halves of the heart (48 mm/s over the rear half and 29 mm/s over the front half). Number of peristaltic waves per series (i.e. between successive reversals) varied from 20 to 178. Duration of each series varied from 120 s to 690 s. Wave frequency ranged from 8 to 21 per min. Reversal frequency ranged from 5 to 30 reversals per hour. Most preparations showed periods of reduced heart activity (“rest periods”) during the the 2 4 h of the experiment. All showed spasmodic contractions of the mantle muscles which caused pressure “surges” in the vascular system. It is shown that, in both directions of beat, most or all of the pressure wave is contributed by the front half of the heart (half towards which peristaltic wave is travelling). This can be related to the “reversed spiral” structure of the heart: each “half” of the heart (i.e. each spiral) serves primarily as the pump for one direction.